1. Field of the invention
This invention relates to improvements in an expanding broadhead arrowhead.
More particularly, the present expanding broadhead arrow has two stages of expansion. The first stage partially expands the arrow head when forward momentum is exhorted onto the arrow, and the second stage fully expands the broadhead arrow when the tip of the arrow makes contact.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98.
In archery hunting it is desirable to pierce an animal with a broadhead arrow that can quickly kill the animal and can leave a blood trail that can be tracked to locate the animal. Broadhead arrows create additional drag because of the broad tip of the arrowhead. Broadhead blades which are exposed during flight often result in undesirable steering of the front portion of the arrow, causing the arrow to deviate from a perfect flight path that coincides with a longitudinal axis of the arrow shaft, when loaded or drawn within an archery bow. Reducing the surface area of a broadhead blade, the undesirable steering effects can be reduced. However, by reducing the surface area of a blade, the cutting area within a target or game is also reduced, resulting in a less effective entrance and exit wound.
Conventional blade-opening arrowheads have been designed so that a substantial portion of the blade is hidden within the body of the arrowhead, such as during flight of the arrow. Upon impact, such blades are designed to open and thereby expose a cutting surface or sharp edge of the blade. When the blades of such conventional arrowheads are closed and substantially hidden within the body, the exposed surface area is reduced and thus produces relatively less undesirable steering effects.
When an arrow is sent the shock of sending the arrow can inadvertently open an arrowhead. To maintain the blades in a closed position during flight. Upon impact, such annular retaining rings are designed to sheer or roll back along the opening blades, in order to allow the blades to move to an open position. Quite often, such conventional annular retaining rings are prone to cracking, particularly when the elastomer material dries out. A number of patents and or publications have been made to address these issues. Exemplary examples of patents and or publication that try to address this/these problem(s) are identified and discussed below.
U.S. Pat. No. 5,066,021 issued Nov. 19, 1991 to Paul V. DeLicia discloses an arrow system where impact with the tip of the arrow initializes blade opening. The blades continue to open as the arrow enters into the animal. A glancing blow will not open the blades because they are not sufficiently exposed to make contact with the hide of the animal.
U.S. Pat. No. 5,083,798 issued Jan. 28, 1992 to Douglas J. Massey discloses an expanding broadhead for an arrow. This patent uses an internal slug that moves forward upon impact to open the broadhead. Forward inertial as the arrow is launched has no effect on the inertial slug.
U.S. Pat. No. 8,197,367 issued Jun. 12, 2012 to Larry R. Pulkrabek et al discloses an expandable broadhead with rear deploying blades. The blades are retained in a slot and forces on the ends of the blades slide the blades into an open orientation. With this design a glancing blow will not open the blades because they are not sufficiently exposed to make contact with the hide of the animal to slide one or both of the blades open.
Published U.S. Patent Application number 2003/0153417 that published on Aug. 14, 2003 to Bruce Barrie et al., discloses an expanding broadhead. Upon impact or deceleration of the arrow the blades will translate backward to an exposed condition. While this patent discloses expanding blades, because the initial force required opening the blades can be high to prevent pre-mature opening as the arrow is initially launched.
What is needed is an expanding broadhead arrow where the arrow is set when launched so that it opens easily upon impact of the tip of the arrow. The proposed broadhead arrow with two-stage expansion provides a solution to this problem.